Paging receiver with a display function that inhibits display of a received command signal

ABSTRACT

A paging receiver with a display function allows a conventional message to be displayed and a receiver control signal to be sent together in a single message format. A first and a second predetermined character are detected in a received message. A message occurring between the first and second characters is extracted as a receiver control signal and is not displayed on a display.

BACKGROUND OF THE INVENTION

The present invention relates to a paging receiver with a displayfunction which allows an ordinary message to be displayed and a receivercontrol signal to be transmitted and received together in the form of asingle message.

With a prior art paging receiver having with a display function, it hasbeen customary to separately send a conventional message to be displayedand a receiver control signal which is adapted for the registration anddeletion of an address for the reception of information, alert controlor similar purposes. That is, it has been impractical to send themtogether in a single message format. An example of a paging receiver ofthe kind described is disclosed in Japanese Laid-Open Patent Publication(Kokai) No. 62-239726 (corresponding to U.S. patent application Ser. No.035,348, European Patent Application No. 87303013.4, Canadian PatentApplication No. 534,391, Australian Patent Application No. 71377/87,Korean Patent Application No. 3486/1987, and Taiwan Patent ApplicationNo. 76101975).

The paging receiver disclosed in this Patent Publication is capable ofreceiving a call number assigned to that receiver (A call) and anothercall number adapted for an information service which is available for anumber of unspecified receivers (B call). The receiver is allowed to orinhibited from receiving the information survice which is based on the Bcall to a group of unspecified receivers, depending upon whether or notit detects a predetermined pattern (e.g. "space", "+" or "-") in amessage which is added to the A call. More specifically, the receiverdisplays a message such as "OUT SERVICE" when the receiver is inhibitedfrom receiving the information service and a message such as "INSERVICE" when it is allowed to receive it.

As stated above, with a prior art paging receiver having a displayfunction, it is impossible to send a receiver control signal and aconventional message in the form of a single composite message. Forexample, when a subscriber who owns the receiver is excluded from aninformation service, a message notifying the subscriber of theinhibition of reception of the information service such as "INFORMATIONSERVICE XX NOT OFFERED. FOR DETAILS, CALL XX-XXXX. X MONTH X DAY XXSERVICE CORP." cannot be sent together with a receiver control signalwhich disables the receiver from receiving the service. On the otherhand, since a different pattern has to be pre-assigned to each receivercontrol function, it is difficult to provide the receiver with an extracontrol function after an information service has been initiated. Forexample, assume that only the receiver control function for "allowingand inhibiting the reception of an information service" is availablewith the receiver at the beginning of the service. Then, when an extrafunction of "energizing a speaker only when important information issupplied" is provided in addition to the above-mentioned receivercontrol function after the start of the service, the old versionreceiver fails to recognize a receiver control signal representative ofthe extra function and therefore erroneously displays it as an ordinarymessage.

SUMMARY OF THE INVENTION

It is therefore an object of the present invention to provide a pagingreceiver with a display function which allows an ordinary message to bedisplayed and a receiver control signal to be transmitted and receivedin the form of a single message.

It is another object of the present invention to provide a generallyimproved paging receiver with a display function.

A paging receiver with a display function of the present inventioncomprises a receiver section for receiving and demodulating a carrierwave which has been modulated by a paging signal and a message signalwhich follows the paging signal and contains a message, a decodersection for comparing the paging signal demodulated and a predeterminedstation's own paging signal which is assigned to the receiver. If thedemodulated and station's own paging signals are coincident, outputtingthe message signal follows the paging signal. The paging receiver alsoincludes a non-volatile memory storing the own station's paging signaland an operation mode of the receiver, an alert section for alerting auser of the receiver to reception of a call by the use of sound, lightor similar means, a display section for displaying the message received,and a control section responsive to the message signal from the decodersection for controlling the alert section and causing the displaysection to display the message.

The control section is provided with message reception control meanswhich comprise first comparing means for comparing a predetermined firstcharacter with the message contained in the message signal which isinputted from the decoder section, second comparing means for comparingthe message received with a predetermined second character, and switchmeans for extracting the received message which appears from an instantwhen the first comparing means detects the first character in thereceived message to an instant when the second comparing means detectsthe second character in the received message. The message extracted bythe message reception control means is treated as a receiver controlsignal and is not displayed by the display section.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other objects, features and advantages of the presentinvention will become more apparent from the following detaileddescription taken with the accompanying drawings in which:

FIG. 1 is a schematic block diagram of a paging receiver with a displayfunction embodying the present invention;

FIG. 2 shows a specific format of a paging signal applicable to thepresent invention (CCIR No. 1 code);

FIG. 3 is a block diagram schematically showing message receptioncontrol means which is included in the paging receiver of FIG. 1 andimplemented by hardware;

FIG. 4 is a schematic block diagram showing a specific construction ofswitch means is included in the message reception control means;

FIG. 5 is a timing chart which is useful for understanding the operationof the circuitry shown in FIGS. 3 and 4;

FIG. 6 is a flowchart demonstrating the operation of the messagereception control means which is implemented by software; and

FIG. 7 is a flowchart representative of a specific receiver controlprocedure in accordance with the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring to FIG. 1 of the drawings, a paging receiver with a displayfunction embodying the present invention is shown and generallydesignated by the reference numeral 10. As shown, the paging receiver 10is generally made up of a receiver section 101, a decoder section 102, anon-volatile memory 103, a control section 104, an alert section 105,and a display section 106. The receiver section 101 receives anddemodulates a carrier wave which has been modulated by a paging signaland a message signal which follows the paging signal. The decodersection 102 compares the demodulated paging signal with its ownpredetermined station's paging signal. When demodulated paging signal iscoincident with the station's own paging signal. The control section 104is activated while feeding the message signal to the control section104. The non-volatile memory 103 stores therein the station's own pagingnumber and an operation mode which is available with the receiver 10.

When a power switch, not shown, of the receiver 10 is turned on, thecontrol section 104 reads the station's own paging number and theoperation mode out of the memory 103 to load them in the decoder section102. Upon the arrival of a message signal, the control section 104energizes the alert section 105 while displaying the received message onthe display section 106. The alert section 105 informs a person who ownsthe receiver of the arrival of a call by the use of sound, light or asimilar alerting means.

The paging signal applicable to the present invention may be implementedby the CCIR No. 1 code (POCSAG code). As shown in FIG. 2, messages (a₁,a₂, a₃, . . . , s₁, c₁, c₂, c₃, . . . ) are error-correction coded usinga BCH code. Applying error control to the output of the receiver section101, the decoder section 102 produces a message signal d₁ (a₁, a₂, a₃, .. . , s₁, c₁, c₂, c₃, . . . ), as shown in FIG. 5. The messages areimplemented by alphanumeric characters which are standardized by ISO646. Predetermined first and second characters S1 and S2 are usuallyselected from "control characters", i.e., those characters which areindicated in the first and second columns of Table 1 shown below.

                                      TABLE 1                                     __________________________________________________________________________    Alpha-numeric Character Set                                                   (Extracted from ISO 646)                                                      __________________________________________________________________________     ##STR1##                                                                     __________________________________________________________________________              0 0 0 0 0   NUL   TC (DLE)                                                                            SP  0   P   P                                         0 0 0 1 1   TC (SOH)                                                                            DC    !   1 A Q a q                                         0 0 1 0 2   TC (STX)                                                                            DC    "   2 B R b r                                         0 0 1 1 3   TC (ETX)                                                                            DC      (#)                                                                             3 C S c s                                         0 1 0 0 4   TC (EOT)                                                                            DC    $ (□)                                                                  4 D T d t                                         0 1 0 1 5   TC (ENQ)                                                                            TC (NAK)                                                                            %   5 E U e u                                         0 1 1 0 6   TC (ACK)                                                                            TC (SYN)                                                                            &   6 F V f v                                         0 1 1 1 7   BEL   TC (ETB)                                                                            '   7 G W g w                                         1 0 0 0 8   FE (BS)                                                                             CAN   (   8 H X h x                                         1 0 0 1 9   FE (HT)                                                                             EM    )   9 I Y i y                                         1 0 1 0 10  FE (LF)                                                                             SUB   *   : J Z j z                                         1 0 1 1 11  FE (VT)                                                                             ESC   +   ; K [ k {                                         1 1 0 0 12  FE (FF)                                                                             IS (FS)                                                                             '     L   l |                                1 1 0 1 13  FE (CR)                                                                             IS (GS)                                                                             -   = M ] m }                                         1 1 1 0 14  SO    IS (RS)                                                                             .     N   n                                           1 1 1 1 15  SI    IS (US)                                                                             /   ? O                                                 o DEL                                                             __________________________________________________________________________

FIG. 3 shows a specific construction of a message reception controlmeans which is included in the control section 104 and is implemented bythe disclosed hardware. The message reception control means, generally20, includes an input terminal 201 allocated to the received messagesignal d₁ and an input terminal 202 allocated to a signal m which showsthat the receiver 10 is receiving a message. First comparing means 203compares the message signal d₁ with a predetermined first character (s₁)If the message signal d₁ is coincident with the character s₁, comparingmeans 203 a first character detect signal r₁. On the other hand, secondcomparing means 204 compares the message signal d₁ with a predeterminedsecond character (s₂) and, if they are coincident, outputs a secondcharacter detect signal r₂. Switch means 205 inhibits the input messagesignal d₁ from being fed to the display section 106 until the secondcharacter detect signal r₂ arrives at the switch means 205. The messagesignal d₁ is regarded as a receiver control signal. The output signal d₂of the switch means 205 is fed out via an output terminal 206.

The switch means 205 of the message reception control means 20 is shownin detail in FIG. 4. In FIG. 4, the first character detect signal r₁ andthe second character detect signal r₂ are applied to input terminals 301and 302, respectively. The signal m used for the above-mentioned purposeis applied to an input terminal 303 while the received message signal d₁is applied to an input terminal 304. The switch means 205 includes an SRflip-flop 305, a delay circuit 306 for delaying the second characterdetect signal r₂ by a period of time which is associated with onecharacter to produce a delayed signal r₃, an inverter 307, an OR gate308, an AND gate 309, and a switch 310 for outputting the receivedcharacter signal d₂ only when the output of the AND gate 309, i.e.,selection signal s is active. The received character signal d₂ isdelivered to an output terminal 311.

The first character detect signal r₁ is fed to an R terminal of the SRflip-flop 305 while the second character detect signal r₂ is applied tothe delay circuit 306 to become the delayed signal r₃ and then routed tothe OR gate 308. The OR gate 308 ORs the delayed signal r₃ and thesignal m which is applied thereto via the inverter 307, the resultingoutput of the OR gate 308 being fed to an S terminal of the flip-flop305. The AND gate 309 produces AND of the output of the SR flip-flop 305and the signal m to produce a section signal s which is active.

The operation of the above circuitry will be described with referencealso made to FIG. 5. Assume that a sequence of received charactersignals d₁ have arrived. The character signal sequence d₁ includes afirst character signal s₁ and a second character signal s₂ which arerespectively representative of the beginning and the end of a receivercontrol command. The signal m remains active while the character signalsequence d₁ appears. The SR flip-flop 305 is held in a set conditionwhen no message is received. Upon the start of the reception of amessage, the signal m and therefore the selection signal s from the ANDgate 309 becomes active. When the first comparing means 203 detects thefirst character signal s₁ in the signal sequence d₁, it produces thefirst character detect signal r₁. This signal r₁ resets the SR flip-flop305 so that the selection signal s is made inactive. As a result, theswitch 310 is turned off to prevent the signal sequence from advancingtherethrough.

As soon as the second comparing means 204 detects the second charactersignal s₂ in the signal sequence d₁, it produces the second characterdetect signal r₂ and delivers it to the delay circuit 306. The output r₃of the delay circuit 306 which has been delayed by one character interms of time is fed to the SR flip-flop 305 to reset this flip-flop305. Consequently, the selection signal s becomes active again to turnon the switch 310 so that the received character signal d₂ is outputted.When the message is fully received, the signal m and therefore theselection signal s becomes inactive to turn off the switch 310.

Referring to FIG. 6, there is shown in a flowchart the operation of themessage reception control means which is included in the control section104 (FIG. 1) and is implemented by software. The procedure shown in FIG.6 begins when a message is inputted from the decoder section 102 afterthe station's own address. The control means in section 104 initializesa switch flag SW to (logical) ONE in a step 601. In the subsequent step602, the control means determines whether or not a message has endedand, if it has ended, executes receiver control processing (step 610)and message display processing (step 611). If the answer of the step 602is NO, one character of the received message is inputted to betemporarily stored in a register C in a step 603 (The character storedin the register C will be referred to as the inputted character C). In astep 604, the inputted character C and the predetermined first characters₁ are compared and, if they are coincident, the switch flag SW is resetto (logical) ZERO in a step 605. Then, the inputted character C iscompared with the predetermined second character s₂ in a step 606 and,if they are coincident, the switch flag SW is set to ONE in the step606. The logical state of the switch flag SW is checked in a step 607.If the switch flag SW is ONE, the inputted character C is determined tobe a part of a message which should be displayed and, in a step 608,stored in a display buffer. If the switch flag SW is ZERO, the characterC is identified as constituting a part of a receiver control command andis stored in a receiver control command buffer (step 609). The messagedisplay processing performed in the step 611 is such that the messagestored in the display buffer is read out and displayed on the displaysection 106. At the same time, the alert section 105 is driven to alertthe user to the message.

A specific receiver control routine will be described with reference toFIG. 7. As shown, when the first character C1 of a receiver controlcommand is a predetermined character C_(on) as determined in a step 701,an address designated by the second character C2 is conditioned forreception (step 702). More specifically, an address reception sets a bitin the non-volatile memory 103 while, at the same time, the address isregistered in the decoder section 102. In this condition, an informationservice may be received by using that particular address until anaddress reception inhibit command which will be described arrives. Ifthe first character C1 of the receiver control command is apredetermined character C_(off), an address designated by the secondcharacter C2 is conditioned for inhibition (step 703). Morespecifically, an address reception inhibit bit of the memory 103 isreset and the address in the decoder section 102 is deleted. Then, thereceiver is inhibited from receiving the information service by usingthe address until the above-mentioned address reception allow commandarrives. Characters other than C_(on) and C_(off) are reserved for useas the first character C1 in order to implement future addition of extrafunctions, step 704.

In summary, it will be seen that the present invention provides a pagingreceiver with a display function which allows a conventional message tobe displayed and a receiver control signal to be sent together in asingle message format, thereby effectively promoting various kinds ofinformation services and facilitating future addition of extrafunctions.

Various modifications will become possible for those skilled in the artafter receiving the teachings of the present disclosure withoutdeparting from the scope thereof.

What is claimed is:
 1. A paging receiver with a display functioncomprising:non-volatile memory means for storing an identification inthe paging receiver and for storing an operational mode of saidreceiver, said identification being preassigned to said receiver as itsown paging signal; receiving means for receiving and demodulating acarrier wave which has been modulated by a paging signal and a messagesignal which follows the paging signal and contains a message, therebyproducing a demodulated paging signal, the character signals S₁ and S₂capable of being inserted in any position in a message signal, but onlywhen control data is necessary; all of the ordinary messages, signals s₁and s₂, and control data having the same format; decoding means forcomparing the demodulated paging signal and a predetermined station'sown paging signal and, if the demodulated and station's own pagingsignals are coincident, outputting the message signal which follows thepaging signal; alerting means for alerting a user of said receiver to areception of a call, said alerting being by sound, light or similarmeans; displaying means for displaying the message received; and controlmeans responsive to the message signal from said decoding means forcontrolling said alerting means and causing said displaying means todisplay the message; said control means being provided with messagereception control means which comprises first comparing means forcomparing a predetermined first representative of the character signalS₁ character with the message contained in the message signal which isinputted from said decoding means, second comparing means for comparingthe message received with a predetermined second representative of thecharacter signal S₂ character, and switch means for extracting thereceived message which appears during a period beginning with an instantwhen said first comparing means detects the first character in thereceived message and ends with an instant when said second comparingmeans detects the second character in the received message; the messageextracted by said message reception control means being treated as areceiver control signal which is not displayed by said displaying means.2. A paging receiver with a display function comprising:non-volatilememory means for storing an identification in the paging receiver andfor storing an operational mode of said receiver, said identificationbeing preassigned to said receiver as its own paging signal; receivingmeans for receiving and demodulating a carrier wave which has beenmodulated by a paging signal and a message signal which follows thepaging signal and contains a message, thereby producing a demodulatedpaging signal; decoding means for comparing the demodulated pagingsignal and a predetermined station's own paging signal and, if thedemodulated and station's own paging signals are coincident, outputtingthe message signal which follows the paging signal; alerting means foralerting a user of said receiver to a reception of a call, said alertingbeing by sound, light or similar means; displaying means for displayingthe message received; and control means responsive to the message signalfrom said decoding means for controlling said alerting means and causingsaid displaying means to display the message; said control means beingprovided with message reception control means which comprises firstcomparing means for comparing a predetermined first character with themessage contained in the message signal which is inputted from saiddecoding means, second comparing means for comparing the messagereceived with a predetermined second character, and switch means forextracting the received message which appears during a period beginningwith an instant when said first comparing means detects the firstcharacter in the received message and ends with an instant when saidsecond comparing means detects the second character in the receivedmessage; the message extracted by said message reception control meansbeing treated as a receiver control signal which is not displayed bysaid displaying means; said switch means comprising: a delay circuit fordelaying a second character detect output of said second comparing meansby a period of time which is associated with one character; an inverterfor inverting a signal which shows that reception of a message is underway; an OR gate for ORing of an output of said delay circuit and anoutput of said inverter; a flip-flop circuit to which a first characterdetect output of said first comparing means and an output of said ORgate are applied; an AND gate for producing a selection signal by ANDinga signal which appears during reception of the message and an output ofsaid flip-flop; and a switch for ouputting the extracted message onlywhen the selection signal is active.
 3. A method of paging a subscriberequipped with a paging receiver having a display function, said methodcomprising the steps of:(a) storing in a paging receiver an addresssignal which is preassigned to identify it; (b) demodulating in saidreceiver a received signal which includes a paging signal followed by amessage signal transmitted in a single format, said demodulated messagesignal including a message signal d₁ containing first and second signalsS₁ and S₂ which respectively mark a beginning and an end of a receivercommand control signal period; (c) comparing said stored address signalwith said demodulated paging signal to determine whether the call isdirected to the receiver, comparing stored characters S₁ and S₂ with themessage signal d₁ and introducing a measured delay responsive to saidsignals S₁ and S₂ for providing a measured time period which is saidreceiver command control signal period; (d) displaying the demodulatedmessage signal in response to said comparison of step (c) finding thatsaid demodulated paging signal is the same as said stored addresssignal; (e) giving alert signal in response to said comparison of step(c) finding that said demodulated paging signal is the same as saidstored address signal and (f) switching a circuit to inhibit a displayresponsive to any signals which appear in said message signal d₁ betweensaid first and second signals S₁, S₂ while enabling a display responsiveto any signals which appear in said signal format after said signal S₂in response to a detection of a call to said receiver during step (c).4. The method of claim 3 and the added step of providing predeterminedbut unused characters in said received signals, whereby said unusedcharacters are available for additional functions in the future.